Ground retaining walls such as the basement walls of a house or an outdoor earth terracing wall are commonly fabricated in the form of a poured slab of steel bar reinforced concrete, the slab resting on edge upon a poured concrete footing. Typically, such slab walls are poured utilizing concrete forms defining a wall between six and ten inches in thickness; a typical thickness for a residential basement wall being eight inches. Typically, such walls have a ground material retaining side, the ground material retaining side having a water proofing coating applied thereto.
Upon construction of, for example, a poured concrete basement wall, ground material is back filled to ground level around the outer periphery of the basement causing the dirt to "lying???? directly against the ground material retaining side of the wall. Under normal circumstances loading forces associated with such ground material fill are directed downwardly, applying insignificant horizontal pressure upon the basement wall. However, on occasion, ground material filled against the ground material retaining side of a basement wall will creep or shift horizontally. Where horizontal movement of ground material occurs in the vicinity of a basement or terracing wall extreme pressures in the horizontal direction may be imposed upon the wall, causing the wall to tilt in the direction of the pressure. Where the upper edges of a basement concrete wall serve as a footing for above ground structural walls of a building, even slight tilting of the basement walls may cause severe structural damage.
A known method for straightening a tilted poured concrete basement wall comprises steps of drilling an aperture completely through the basement wall; driving by means of jack hammer a spirally threaded shaft through the aperture to extend eight to ten feet beyond the basement wall into the ground, leaving a spirally threaded end of the shaft extending into the basement; mounting a drawing plate and a spirally threaded nut over said spirally threaded end; excavating a pit in the ground material to expose the opposite end of the threaded shaft; attaching a ground anchor or a deadman to said opposite end; and progressively tightening the threaded nut, pulling the drawing plate and the basement wall outwardly along the shaft. A drawback or deficiency of such known method is that the deadman or anchor must be positioned relatively close to the basement wall due to difficulties in driving steel shafts an extended distance through ground material. Where a basement wall tilts due to horizontal ground pressure, it is often undesirable to place an anchor or deadman in close proximity with the wall, since the same forces which press inwardly upon the basement wall may simultaneously act upon the anchor. Thus, it is desirable to position the anchor an extended distance from the wall. Another drawback or deficiency of the above described known method is that drilling a shaft receiving aperture through the basement wall allows water seepage into the interior spaces of the basement. Another drawback or deficiency of the above described method is that an unsightly nut and drawing plate is necessarily exposed within and operated from the interior spaces of the basement.
The instant inventive assembly and method solves all of the above defects and deficiencies by providing a flexible cable spanning between an exterior surface of a basement wall and an anchor or deadman, and by providing a jackscrew pulling mechanism operable from ground level for pulling the cable and drawing the basement wall toward the ground anchor.